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26 Comments
fithisux
While the world does AI I learn assembly
myles-hn
Same. But mine was an android app. github.com/crouther
kstrauser
Where’s the math actually done, on device or on your server?
Feedback: the compound interest calculator doesn’t support continual compounding? That’s surprising, and also the easiest to compute.
tonetheman
[dead]
ysofunny
https://planetcalc.com/
4887d30omd8
You're not the only one. I recently took up running and didn't particularly like any of the existing running pace calculators, so I made my own: https://calcubest.com/health/runningpace
And then kinda realized that there were others I wanted to have, and a few I thought others might want, so I added more.
A calculator is simple enough that it's fun to work on one when I need a break from something more complex but want to be able to do something other than doom scrolling. So now every couple of weeks I add another one.
jrockway
I like `units` for unit conversion. It's in the default install of MacOS, so readily accessible for most people.
redbell
Somehow related:
“A calculator app? Anyone could make that”: https://news.ycombinator.com/item?id=43066953
stanleykm
One calculator I’ve come to love over the years is Numi. I keep it open all day every day and it does a pretty good job of bridging the gap between the typical skewmorphic calculator app and scilab or python. It’s a text based calculator that allows you to declare variables and do unit and base conversions and save and load your work. No graphing though unfortunately and i dont think it really has much in the way of plugin support.
Anyway not to say your calculators arent useful op, i just think that something that can be open on the desktop is more useful than something that is hidden in a chrome browser tab.
bityard
If you're taking suggestions, I have a frequent need to do basic arithmetic on fractions and not many "app" calculators do that well or at all.
ikhare
On the topic of calculators. I discovered Figr[1] on HN a while ago, and it really helps when doing one off multi variable thing, like helping a customer estimate their bill etc.
Kudos on building this. I occasionally search for these on Google and am always disappointed by the mess. Bookmarked.
[1] https://www.figr.app/
bvanderveen
A random dimensional analysis that I find amusing about fuel consumption units:
liters / 100 km => m^3 / m => m^2
(volume) / (distance) => (area)
This can be interpreted as the cross-sectional area of a hypothetical trough of fuel running alongside the road, whose contents you slurp up and consume in your engine as you pass (in lieu of using fuel stored in an onboard reservoir).
noduerme
This is great. I really think that having a theme to iterate on is the best way of revisiting coding/math skills and learning new ones. And building things from scratch is so much more rewarding than snapping parts together. My free time right now is trying to rewrite 90s screensavers down to the rasterizer level, without consulting anything for how to do stuff like antialiasing.
One little note, just checking out your loan calculator: On my phone, the total interest div is cut off at the decimal point, and the total payment overflows the nice round rect holder. You could dial in the font size scaling with a bit of custom Javascript there. They stand out, too, because they're bottom line figures.
BigParm
This is dope
wendyshu
Can't Wolfram Alpha do this?
rishikeshs
I started something similar recently: https://calcbun.com
They key is finding unique calculators.
lelandfe
If I calculate something, hit back in my history, and then return, what I had entered is wiped out.
If I enter text into this HN comment box, hit back in my history, and then return, what I've typed is maintained.
karparov
A suggestion for your speed converter: different sports use different units which your converter could support as well.
A few examples:
Running usually measures pace in minutes per kilometer or mile. That will be extra fun for you since it wouldn't be 4.33333 min/km but would be written as sth like 4:20 min/km.
Swimming uses min/100m or sec/100m.
Rowing uses min/500m.
If you add these then I'd be using this a lot!
aredox
AI can't calculate anyway, so, you're doing good.
opem
Loved the title! XD
4ndrewl
Loser. I bet you missed out on the metaverse. And blockchain.
Seriously, this is great – solving problems for users seems to be hugely underrated here.
Uptrenda
inspiring in a weird way. maybe there is hope for engineering afterall.
chrismorgan
Some comments, based purely on https://www.calcverse.live/calculators/bmi.
• Keyboard accessibility is suffering, because the buttons aren’t associated with a form. Most notably, pressing Enter when one of the text boxes is selected doesn’t do anything. You should put everything inside a <form> element, and then if you’re using <button>, decide whether it’s type=button or type=submit.
• A tad more subjective, but actual radio buttons are better than the buttons you’ve used for Metric/Imperial.
• As it stands, they lack a keyboard focus indication. (And the submit button has poor focus indication.)
• People don’t talk about heights in inches. They talk about them in feet and inches. You want to be able to accept feet and inches as two separate inputs. Not everyone who knows that their height is X′Y″ knows that means 12X+Y inches, and even more will make a mistake in calculating that, or just give up.
• If you switch between metric and imperial, and there’s a number in height or weight, it should probably convert the number to the chosen scale.
• If you just recalculated on input rather than on submit click, the experience would probably be smoother.
• Colour contrast on “Category: Overweight” is definitely too low. “Category: Normal weight” is also a little too low; underweight and obese are fine.
• Consider sometimes what related information might be useful. Every BMI calculator lists the categories, but something I somehow haven’t ever seen and yet which would be very useful for giving someone something to aim for is a mapping: for a given height, what weights do the categories correspond to? e.g. for 200cm, underweight = 0–74kg, normal weight = 74–100kg, overweight = 100–120kg, obese = 120–∞kg. Consider visualisations too. And mentioning what the calculation actually is that is being performed. Calculations are simple. Presenting them well is the harder bit.
newbie578
On wide screens the app is not centered, add some margin auto.
hkt
Bless you. Keep fighting the good fight.
ninalanyon
BMI calculators are dangerous tools in uncritical hands. Here is a link to the UK NHS page that provides such a calculator but only after it has described some of the limitations:
https://www.nhs.uk/health-assessment-tools/calculate-your-bo…